ISA T 2000 - 4: VT Tests: Voltage Withstand

DOC. MIE11110 Rev. 5
Page
64
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110
Purpose of the test is to measure the actual VT ratio, and to
verify its polarity. This test is performed applying voltage to the
primary side, and measuring the secondary voltage and phase
angle. The connection to the loads can be open or closed, in order
to verify the accuracy error caused by the burden.
The test procedure is the same as the one described in paragraph
1.1.1. The only difference is the value of the secondary voltage,
typically much lower than with a standard voltage transformer.
1.2.4: VT tests: voltage withstand
When this test is selected, the following menu is displayed.
Purpose of the test is to verify the VT isolation, and to measure
the corresponding leakage current.
This test is performed applying the high voltage between
secondary and ground, and measuring the corresponding current